Cooling Fan Out of Balance

The cooling fan spins out of balance when idling. When you press on the gas it spins even more out of whack and hits the plastic protection covering the fan. What causes this out of balance spinning and what would the fix cost me?

check fan bolts and also check water pump bearings being worn out grab ahold of fan blades with both hands and see if it wiggles up and down or back and forth if it does either fan bolts are loose or water pump is bad. jerry

any one out there had to have the fan clutch replaced on any trailblazers made in 2002 up to the present. I have had two replaced . I called g.m they said they have had no major problems with this.It cost approximately parts and labor 800.00 each time.My trailblazer has 30000 original miles on it. I have had it seven years. just use it for vacations. also any control modulators for heating and air been replaced,I have bought 4 new chevrolets over the past ten years, probably no more , they donot stand behind their products anymore

I have replaced the fan clutch once so far. At about 3 years old. Chevy told me what they told you, they don't have problems with the clutch. When the clutch ws shot the truck sounded like a harrier jump jet taking off, nothing but extremely loud whirring noise. A friend helped me with the replacement. You have to take out a lot of stuff in the front like the radiator. You also need to disconnect the transmission cooling lines that got to the radiator. If I remember correctly the clutch cost about $250 or so. I also needed to get a special wrench.

I have a 2003 TB with 130,000 mi on it, It has been well maintained and have only done brakes & one water pump.Runs like a charm and gets about 18 mi per gal on a trip.I recently replaced the water pump as it had quite a bit of play in the bearings (but didnt leak) I have replaced waterpumps before & was quite surprised at this one. It was no bigger than a soup can. It was a chore removing all the crap to get to it. I thoght I could sneek it out with out pulling the radiator but it was too close a fit. I thought that after replacing it it would eliminate my whirring/fluttering sound from the engine after hitting hard bumps.. No luck...it still makes the sound. I tried shutting the engine off while in Neutral and it still is a pronounced noise but stops at around 10 mi an hour.I am suspecting the fan clutch. I have looked online for one and found that they vary greatly in price. One was $168.00-$178.00. They have a plug on them that plugs into a sensor. My original does not have that.I have found other replacements for $60 & $80 that match mine more than these others with the electronic add-on. Anyone know why this one would be cheap?(er) when everyone else was charged $6-$800.00 for replacement????

All TB's have the viscous clutch fan. It's not a sensor, it's the connection for the current that controls the viscosity of the fluid in the fan clutch to vary the fan speed independent of the engine speed.

i have a 2003 trailblazer, had problem with loud noise from clutch fan. sounds like a airplane when first start up. continues to run high for about three or four blocks. no problem with cooling system, the dealership determined the clutch fan was going out. suggested i replace it also since the radiator was out, best to replace the water pump as it could go out , and of the thermostat, well, this cost me over 1000.00 dollars. four months later, same noise, after going back to dealer, seems there is no problem as the dealer now claims, just natural sound trailblazers make. still driving, take off sound and all.

The trailblazer still is making the noise. I have isolated it to the right front wheel. After I hit a hard bump on the rirght side Is when the noise occures any where from arond 30 to 45-50 mph. It woulnt stop making the noise unless i pulled over and almost come to a complete stop. I continued playing around trying to isolate it & and found out that when the noise occured & I switched to allwheel drive it would go away completely. I mentioned this to a guy who works on trucks and he came over & pulled & yanked on a few different things & it appears that the axel on the passenger side moves about a good 1/2" in all directions. This is where it comes out of the transmission/engine? is this an easy fix or expensive fix? can it be done by a handy do it yourselfer??? :sick:

I started this thread and forgot about it. Basically, it ended up that the water pump was going bad and was causing the fan to wobble. Had to replace the water pump and all is well now and still going strong after a year.

water pump has gone out, locked up and broke belt. can anyone let me know if this might be something I can do myself or if it needs a pro. how much stuff has to be taken off to replace, and if anyone has an idea of what the cost might be on one.

hi my name is rudy and i just had my fan clutch replace and i did it my self is so eazy. u dont have to pay 800$ i replace the water pump too is working fine now it only cost me like 250 to get it fixed. make sure u check ur conectors,make sure they r not ripped or corroded. and if u replace the clutc 2 times than something else is wrong get a 2nd opinon

hi rudy here i replace water pump myself and is not hard to do just have to take fan out by removing fan clutch and fan cover, to remove the pump is only 4 bolts just buy the repair manual for that car and will show u how to do it. in the book will tell u to remove radiator and other stuff but u dont have to. there is always short cuts (good short cuts ofcourse)

hi i would like to know if there is some one out there to help me. i had a cousin replace my head gaskets and after he was done i had other problems like low oil pressure but only when the car is at a stop or when i warming it up but when i press the gas the needle goes up when i stop the needle goes down. i can hear the timming chain too can some one help thank u